Much of the response to the clever tweet from the covert agency was, as you might expect, dripping with overt sarcasm. Here's a selection:

The CIA has closely monitored social media worldwide as part of its intelligence gathering. As NPR reported in 2011, a group within the agency monitors public Facebook updates and tweets from people overseas, up to 5 million a day.

Kimberly Dozier, a reporter for The Associated Press, told us at the time those activities have led to some successes. She said:

"Well, they have predicted things like — believe it or not — the fallout from the revolt in Egypt, the Arab Spring. I sat down with the director of the center, Doug Naquin, who said that after the Twitter revolution of 2009 in Iran, they had predicted that if something like that took hold in the Middle East — in a country like Egypt — social media could be a game changer. They just couldn't predict when the revolt would happen, and how quickly the fallout would come."

Other covert agencies, including the National Security Agency, are already on Twitter. The NSA, in fact, showed its encryption chops last month when, as NPR's Scott Neuman reported, it sent out the following tweet:

Translation: Want to know what it takes to work at NSA? Check back each Monday as we explore careers essential to protecting your nation.